1. Field of the Invention
The present invention relates generally to cooling devices and, more particularly, to devices especially adapted for cooling integrated circuits.
2. Description of the Prior Art
When integrated circuits are in operation, they generate heat. When heat generation is relatively low, ambient air may be sufficient to cool the integrated circuits. When more heat exchange is needed than can be provided by ambient air, a fan is often employed to exchange relatively large quantities of ambient air for cooling. However, there are certain integrated circuits which generate so much heat that the use of a cooling fan may not be sufficient for cooling the integrated circuits.
Currently, a standard 486-based central processing unit (CPU) or Intel Pentium CPU may run as high as 180 degrees Fahrenheit or higher. With such hot-running integrated circuits, cooling may be a very difficult problem. Such 486-based central processing units or Intel Pentium CPU's are provided with cooling fans, but such cooling fans may not be adequate for providing proper cooling to the CPU's and adjacent components. To assure adequate cooling, it would be desirable is a positive cooling source could be provided for the 486-based central processing unit or Intel Pentium CPU.
In the art of cooling integrated circuits, it is well known to employ the electronic effect known as the Peltier Effect for providing an active cooling device. Devices which operate with the Peltier Effect actually create a cool surface. In doing so, the Peltier Effect also creates a hot surface.
Throughout the years, a number of innovations have been developed relating to cooling integrated circuits with Peltier Effect devices, and the following U.S. Pat. are representative of some of those innovations: Nos. 4,685,081; 5,028,988; 5,040,381; and 5,079,618. More specifically, U.S. Pat. No. 4,685,081 discloses a Peltier junction device that is used for thermal control of solid state devices. This Peltier junction device is electronically controlled for both cooling and heating a solid state bubble memory. For cooling 486-based central processing units or Intel Pentium CPU's there is no need for a heating capability.
U.S. Pat. No. 5,028,988 discloses cooling devices for integrated circuits that employ cryogenics and water cooling. The use of cryogenics requires expensive equipment and complex procedures. Moreover, the use of water for cooling electronic components has its own risks and dangers.
U.S. Pat. No. 5,040,381 discloses an apparatus for cooling circuit modules that includes a Peltier Effect cooling device, a heat sink placed between a circuit module and the Peltier Effect device, and a fin-containing heat radiator attached to the backside of the Peltier Effect device. The Peltier Effect device is laminated between two layers of a polymer based thermally conductive dielectric material. However, the lamination process is an expensive and time consuming process.
U.S. Pat. No. 5,079,618 discloses semiconductor device structures that are cooled by Peltier junctions and electrical interconnect assemblies. With the structures disclosed in this patent, the device that is cooled by the Peltier junction is placed on top of the Peltier junction. Such structures could not be used with 486-based central processing units or Intel Pentium CPU's which are connected to a mother board. In this respect, it would be desirable if a Peltier Effect cooling device for integrated circuits were provided that can be placed on top of an integrated circuit that is connected to a mother board.
There are many computer systems currently in use that employ 486-based central processing units or Intel Pentium CPU's. In view of the heat problems discussed above, it would be desirable if a device were provided which could readily retrofit a 486-based central processing unit (CPU) or Intel Pentium CPU with a Peltier Effect cooling device.
As mentioned above, many computer systems are provided with electrically powered ventilation fans. The power supplied to most electrically powered computer ventilation fans is generally 12 VDC. Peltier Effect devices are available that are also powered by 12 VDC. Thus, it would be desirable for a Peltier Effect cooling device to be retrofitted to a 486-based central processing unit or Intel Pentium CPU that is readily adapted to being powered by 12 VDC electrical power in a computer.
As mentioned above, a cooling device for integrated circuits that employs the Peltier Effect also generates its own inherent heat. If such a Peltier Effect cooling device were retrofitted to a computer that employs a current 486-based central processing unit or Intel Pentium CPU, then an overall added heat load would be added to the existing ventilation fan that is used for cooling the computer. Such an added heat load may exceed the capacity of the original ventilation fan. To overcome the added heat generated by the Peltier Effect cooling device and to remove heat from the 486-based central processing unit or Intel Pentium CPU, it would be desirable for a retrofitted Peltier Effect cooling device for integrated circuits to have its own dedicated ventilation fan. Moreover, it would be desirable for the dedicated cooling fan in a retrofitted cooling device to derive power for running the dedicated cooling fan from the same 12 VDC power source that powers the original ventilation fan.
For a Peltier Effect cooling device that is retrofitted to integrated circuits, the retrofitted cooling device should be an integrated retrofitting module that contains a heat sink that is placed in close proximity to the integrated circuits, that contains a Peltier Effect cooling assembly that is placed in contact with the heat sink, that contains a heat radiator that is placed in contact with the Peltier Effect cooling assembly, and that contains a dedicated ventilation fan that circulates air across the heat radiator.
U.S. Pat. No. 5,150,198 may be of interest for its disclosure of a plate-shaped heat radiator for semiconductor chips. The Peltier Effect is not employed with this device.
Thus, while the foregoing body of prior art indicates it to be well known to use Peltier Effect cooling devices for cooling integrated circuits, the prior art described above does not teach or suggest an integrated circuit cooling apparatus which has the following combination of desirable features: (1) provides a positive cooling source for a 486-based central processing unit or Intel Pentium CPU; (2) does not have a heating capability; (3) does not employ expensive equipment and complex procedures for handling cryogenics; (4) does not use water for cooling electronic components; (5) does not employ an expensive and time consuming lamination process; (6) can be placed on top of an integrated circuit that is connected to a mother board; (7) can readily retrofit a 486-based central processing unit (CPU) or an Intel Pentium CPU with a Peltier Effect cooling device; (8) is readily adapted to being powered by 12 VDC electrical power present in a computer; (9) has its own dedicated ventilation fan for overcoming the added heat generated by a Peltier Effect cooling device and for removing heat produced by a 486-based central processing unit or Intel Pentium CPU; (10) provides an element for securing a Peltier Effect cooling device to integrated circuits; (11) derives power for running a dedicated cooling fan from the same 12 VDC power source that powers the original ventilation fan; and (12) is an integrated retrofitting module that contains a heat sink that is placed in close proximity to integrated circuits, that contains a Peltier Effect cooling assembly that is placed in contact with the heat sink, that contains a heat radiator that is placed in contact with the Peltier Effect cooling assembly, and that contains a dedicated ventilation fan that circulates air across the heat radiator. The foregoing desired characteristics are provided by the unique integrated circuit cooling apparatus of the present invention as will be made apparent from the following description thereof. Other advantages of the present invention over the prior art also will be rendered evident.